Despite years of research into the development of new methods of treatment, cancers of the lymphatic system, or lymphomas, remain quite common. For example, more than 60,000 people in the United States are diagnosed with lymphoma each year, including more than 55,000 cases of non-Hodgkin lymphoma (NHL), and these numbers are constantly increasing. In addition, the prognosis for those affected by these diseases is often poor, as the survival rates for lymphoma patients remain low.
While traditional treatments for lymphoma typically depend on the type of lymphoma as well as the medical history of the patient, first-line treatments typically include chemotherapy. Such chemotherapy generally entails the administration of a mixture of compounds (e.g., the formulation referred to as CHOP that includes cyclophosphamide, doxorubicin, vincristine and prednisone. Cancer treatments also frequently include other forms of therapy (e.g., radiation). In many cases, patients respond initially to such first-line treatments, but subsequently suffer a relapse (e.g., tumor reappears or resumes growing). Following one such relapse, patients are often treated with further chemotherapy, or with other procedures such as bone marrow transplantation. Again, in many cases, patients initially respond to such additional treatments, but subsequently suffer another relapse. In other cases, a patient fails to respond at all to a treatment, even initially, and is thus said to have a refractory cancer. In such cases little agreement exists in the art regarding optimal subsequent treatment.
Thus there remains a need in the art for methods suitable for treating relapsing and/or refractory lymphomas, as well as for treating other poor-prognosis hematopoietic malignancies.